Blindstitch sewing-machine.



W. A. MGGOOL.

BLINDSTITCH SEWING MACHINE.

APPLICATION FILED NOV. so. 1908.

' Patented June 7, 1910.

ANDREW B. G [mm c WILLIAM A. MCCOOL, OF BEAVER FALLS, PENNSYLVANIA, ASSIGNOR TO ACME- KEYSTONE MFG. COMPANY, A. CORPORATION OF PENNSYLVANIA.

BLINDSTITCI-I SEWING-MACHINE.

To all whom it may concern:

Be it known that I, WILLIAM A. MoCooL, a citizen of the United States, residing at Beaver Falls, in the county of Beaver and State of Pennsylvania, have invented or discovered certain new and useful Improvements in Blindstitch Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to certain improvements in the sewingmachine shown by the patent to G. A. Dearborn, No. 67 9,553, granted July 30, 1901; and the invention has for its object to provide a rotary ridge-former or back-guide which is rigidly held in place on its support so that it will always maintain its correct position with relation to the needle, while at the same time it is permitted, in its intermittent rotary movement, to move forward with the work, such rotating ridge-former or back-guide being preferably operated from a yieldingly mounted feed wheel with which said rotating ridge-former or back-guide has a loose connection; so that while the feed wheel is permitted to yield, to accommodate inequalities in the work, or different thicknesses of goods, the cooperative relations of the ridgeformer or back-guide and the needle remain at all times undisturbed.

In the accompanying drawings Figure 1 is a plan View of the work-support of a blind stitch sewing machine with the improvements mounted thereon. Figs. 2 and 8 are partial sectional elevations of the same with the parts in different positions in the two views. Fig. t is a partial sectional end View of the same. Figs. 5 and 6 are side and edge views, respectively, of the rotating ridge-former or back guide and the supporting plate in which it is mounted for rotation.

Referring to the drawings, 12 denotes a pivotally mounted yielding work-support similar to that of the machine of said Dearborn patent, said work-support having integral ears 1?) for the reception of pivot screws 14: on which is mounted a yoke 15 afi'ording bearings for a rotating shaft 16 provided with a ratchet wheel 17* by which it may be intermittingly rotated, said shaft Specification of Letters Patent.

Application filed November 30, 1908.

Patented June 7, 1910.

Serial No. 465,198.

having at its forward end, by means of a ball portion 17, a universal joint connection with the hub 18 of a feed wheel 19 preferably integral with a shaft 20 on which is mounted a second feed wheel 21. The shaft 20 is provided at its outer end with a ball portion 22 received in a concave socket of a bearing pin 23 mounted in an integral part of the work-support 12, and yieldingly forced upward by a plate spring 24; forked at its forward end for engagement with a reduced lower portion of said pin. The yoke 15 is held yieldingly upward against any suitable stop, as a screw 25, by means of a coil spring 26 seated beneath the forward end of said yoke, so that the said yoke and the feed wheels are free to yield downwardly to accommodate inequalities in the work, as indicated in Fig. 3; the shaft 16 having a loose connection, by means of a pin 27, with a slotted portion of the hub 18, thus permitting the feed shaft 20 to have a loose driving connection with the shaft 16 and to be rotated from said shaft 16 by means of the said pin 27 working in suitable slots in said hub 18.

The parts thus far described are similar to the corresponding parts of the machine of said Dearborn patent, and the present in vention relates to the ridge-former or backguide and themeans formounting and rotating the same. from the feed-wheel. Integral with the work-supporting table 12 is a block or portion 28 which is provided with a slit for the reception of a plate 29 having a circular seat or recess of about 240 extent for the reception of the rotating ridgeformer or back-guide 30 which is thus journaled in the said plate 29 and which is of slightly less thickness than the said plate; so that while the latter may be rigidly secured in place in the said block 28 by means of the set screws 31, the said rotating ridgeformer 30 will be free to rotate in the said slit in the block 28 in which said plate 29 is rigidly fixed. The rotating ridge-former 30 is provided with a central slot 82 of considerably larger diameter than the feed shaft 20, so that the latter is free to move down ward in the said opening 32. When the feed shaft yields to accommodate the inequalities in the work, as shown in Fig. 3,

the connection between said feed wheel and the ridge-former must be maintained, and

to this end said ridge-former is provided with a radial slot 33 for the reception of a crank pin 34 with which the feed wheel 19 is provided, so that the said rotating ridgeformer may be intermittingly rotated. with the said feed Wheel while the latter will be free to yield, to accommodate inequalities in the work, and still maintain its connection with the said rotating ridge-former.

. It will therefore be seenthat the invention provides a rotating ridge-former which is mounted for rotation in a bearing which is fixed or rigid relative to the plate or part 12' on which said bearing is supported, so that said ridge-former will always maintain a correct position with relation to the needle 35; while the feed-wheel, from which said ridge-former is intermittingly rotated, is

yieldingly mounted relative to said plate or part so that it will be freexto give to accommodate inequalities in the work. This rotating ridge-former may be adjusted to bring it into proper cooperation with the needle when the set screws 31 are loosened, and when the said set screws are tightened the supporting plate 29 in which said rotating ridge-former is mounted for rotation will be rigidly fixed in place on the plate or part 12, as will be understood. This rotating ridge-former is found to be much better in the operation of the machine than the rigidly mounted ridge-forming rib of the Dearborn patent above referred to, in that the peripheral surface of the rotating ridgeformer moves forward with the work and thus induces a freer movement of the latter, and in that new portions or surfaces of the said rotating ridge-former are being constantly presented to the needle; so that a difficulty which has been found to exist in the machine of the said patent is avoided. This difficulty has resulted from the fact that where the relative adjustment of the I needle and the ridge-forming rib or backguide of the said Dearborn patent is not quite accurate the shaft of the needle will have a rubbing contact with the said ridgeforming rib or back-guide, and soon wears a transverse groove in the same; so that good blind stitching cannot be effected after such groove has been worn in the ridge-forming rib or back-guide; and as with a fixed rib or back-guide the same surface thereof is always presented to the needle a groove is thus liable to be soon worn therein. But with a rotating ridge-former or back-guide this difficulty does not result, in that new portions of the peripheral surface of the ridge-former are being constantly presented to the needle, as above stated.

It has heretofore been proposed to employ rotating ridge-formers in machines of this class, but as in such cases the feed-wheel surface of the ridge-former relative to the needle remains undisturbed.

Having thus described my invention I claim and desire to secure by Letters Patent:

1. In a blind stitch sewing machine, the combination with stitch-forming devices comprising a needle, of a yieldingly mounted rotating feeding device, a rotating ridgeformer independent of said feeding device, a support, independent of said feeding device, in which said ridge-former is mounted for rotation, and a loose operating connection between the said rotating feeding device and'the said ridge-former, whereby said ridge-former will be intermittingly rotated from said feeding device and will occupy a constant position relative to the said needle, but the said feeding device will be left free to yield to accommodate inequalities in the work. V V p 2. In a blind stitch sewing machine, the combination with a yieldingly mounted feed wheel provided with a crank pin, of a rotating ridge-former provided with a slot entered by said crank pin, a plate in which said ridge-former is mounted for rotation and which plate is fixed or rigid relative to said feed wheel, whereby said ridge-former will occupy a constant position relative to its support and be intermlttingly rotated from said feed wheel, but the wlatter'will be left free to yield to accommodate inequalities in the work. 7 i

3. In a blind stitch sewing machine, the combination with a support, as 12, of a feed wheel yieldingly mounted on said support, a bearlng plate, as 29, separate from but rigidly attached to' said support, a ridgeformer mounted for rotation in said bearing plate, and means for rotating said ridgeformer. I

4:. In a blind stitch sewing machine, the combination with a support, as 12, of two feed wheels bothyieldingly mounted on said support, a rotating ridge-former mounted in a bearing fixed to said support and interof but located between said feeding wheels, av

support, separate from or independent of said wheels, in which said ridge-former is mounted for rotation, and a loose operating connection between one of said wheels and the said ridgeformer; whereby said ridgeforrner will be intermittingly rotated from said feeding wheel and will occupy a 0011-.

stant position relative to said needle, but the said wheels will be left free to yield to accommodate inequalities in the work.

In testimon whereof I affiX my signature,

in presence 0 two witnesses.

WILLIAM A. MoCOOL.

Witnesses:

HENRY CALVER, CHAS. S. HYER. 

